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成都市华西医院妇科是公立医院吗内江市第二人民医院看前列腺炎好吗Science and technology科学技术Dealing with asteroid strikes应对小行星撞击A close shave近地掠过After a hit and a near miss minds are focusing on the risks from space rocks在一次撞击和一次近距离擦肩而过后,人们开始关注来自外太空岩石的威胁One close shave with an asteroid is cause for excitement.一次小行星近地掠过是一种刺激,Two on the same day is scary.同一天发生两次就是惊险了。On February 15th planet Earth experienced exactly that, as a hunk of itinerant space rock passed by extremely close.在2月15日,行星地球正经历了这样的惊险:一块流动的大块头太空岩石在咫尺的距离掠过地球,While another exploded spectacularly in the skies above Russia.而另一块则十分壮观得在俄国上空爆炸。The first asteroid, called 2012 DA14, had been known to astronomers for around a year.第一颗小行星名为2012 DA14,天文学家在大约一年前发现。They had calculated that there was no risk of collision. But the 30-metre, 190,000-tonne rock came close: 27,700Km above the surface, inside the orbit of some satellites.他们计算出小行星的轨道,并无撞击危险。但这枚直径30米、重达190000吨的石块离得是那么近:距地表27,700千米,处于一些卫星轨道内。It was the nearest ever recorded for an asteroid that size.对这种大小的小行星,这是有记录以来距离最近的一次。The second came quite literally out of a clear blue sky, appearing without warning and then disintergrating about 30 seconds later over Chelyabinsk.第二颗在一片晴空万里中毫无警告得出现了,约30秒后在车里雅宾斯克市上空解体了。According to NASA, the 10,000-tonne meteor released about 500 kilotonnes of energy when it broke apart, equivalent to the yield of a largish nuclear bomb.来自NASA的数据显示,这颗10000吨重的陨石在肢解时释放了大约500吨质量的能量,相当于一颗大型核弹的爆炸当量。Only the height of the detonation-dozens of kilometers up–kept the fatality count at zero, although more than 1,000 people were injured as windows were blown out of buildings.好在爆炸发生在数十公里的高空,未有人员死亡。虽然有超过1000人受伤,但只是被震碎的建筑物玻璃伤到。This double whammy has focused minds on the threat from asteroids, something that astronomers have long known is real but which tends to be treated with giggles whenever it is brought outside the lab.这次双重晦气已引起人们对小行星威胁的关注。长久以来天文学家们就清楚这种实实在在的威胁,但一旦在实验室外提起就会引来哄堂大笑。Some politicians have nevertheless taken action.不过还是有些政客们采取了行动。In 1998 Americas Congress ordered NASA to begin cataloguing the very largest, planet killer asteroids-defined as those more than a kilometer across.美国国会在1998年下令NASA将那些大型的行星杀手级别的小行星编入目录,直径超过1公里的都归入其中。The agency reckons it has accounted for more than 90% of them.NASA认为超过90%的这类小行星都已记录在案。But as the impact from such a beast would be catastrophic, the few undiscovered rocks still represent a threat.但是由于这种怪兽可能带来灾难性的撞击,少部分未被发现的此类岩石仍然是个威胁。Deep impact深度撞击These days, a mix of national organizations and universities run an alphabet soup of detectors.目前,一群来自不同国家组织和大学的研究人员开始了初步的探测。But the field is still a bit of backwater, and budgets are tight.但是该领域仍是一潭死水,预算很紧张。John Tonry, an astronomer at the University of Hawaii, is building an asteroid-hunting telescope called ATLAS with m from NASA.John Tonry, 一位来自夏威夷大学的天文学家,正在建造一个名为ATLAS的小行星搜索望远镜,NASA提供了500万美元的经费。Dr Tonry cannot afford to hire a proper telescope engineer, and is having to design the device himself.士Tonry负担不起一个正式的望远镜工程师,必须亲自设计这台望远镜。ATLAS is intended to spot mid-sized city killers like 2012 DA14.ATLAS望远镜的目的是为了辨认出类似2012 DA14这样中等大小的城市杀手。Astronomers reckon the risk from these is at least as great as that from the biggest ones because there are many more of them.天文学家估测这类小行星的威胁绝不在那些更大的小行星的威胁之下,因为数量实在太多。Exactly how many more, though, is hard to say because, being small, they are hard to see.不过至于准确数量却很难说,因为他们实在太小难以被发现。ATLAS should be able to spot a rock on a collision course a few days before it hits, giving time to organize a hasty evacuation.ATLAS应该可以提前数天发现一块沿着撞击轨道运行的岩石,争取足够的时间组织快速疏散。Of course, rather than evacuating the impact zone, it would be better if there were some way to deal with a threatening asteroid more directly, by nudging it into a different orbit.当然,比起疏散撞击区域,找到一个更直接应对小行星威胁的方法会更好,比如把小行星推入不同轨道。Asteroid deflection suffers from a even greater giggle factor than asteroid detection, but several ideas have been proposed. One popular method is to use nuclear weapons.让小行星偏向的想法比小行星探测更会招致哄笑,但已经有人提出了一些主意。Detonating a nuke near an asteroids surface could boil away some of the rock and-by Newtons third law of motion-impart a shove in the other direction.一个通俗的方法是使用核武器。在小行星表面附近引爆一枚核弹可以蒸发掉一些岩石质量。根据牛顿第三运动定律,还会在其他方向产生作用力。Done early enough, this would shift the objects orbit sufficiently to stop it hitting Earth.如果爆炸时间足够提前,这足已改变小行星的轨道,防止与地球的撞击。(当然这毫无意义,只是纯粹在卖弄学问罢了。Alternatively, simply ramming the offending rock might provide enough force to provoke a suitable reaction and change in orbit.作为另一种选择,针对来犯岩石的很普通的撞击,也许能产生足够的作用力引发反作用力,进而改变轨道。The European Space Agency plans to launch, in 2015, a spacecraft called Don Quijote that will test the feasibility of doing this.欧洲航天机构计划在2015年发射名为堂吉诃德的太空船,以测试这种方法的可行性。Other ideas are more elegant: painting the rock white, for instance, will alter the way it interacts with sunlight, nudging it into a new orbit.其他的主意要优雅得多:比如把岩石表面涂成白色,这样将改变太阳光对其的作用力,也就改变了运行轨道。Or rocket motors might be strapped to it, to propel it in a desirable direction. Or a large spacecraft could orbit around it, where its gravity would alter the asteroids orbit around the sun.或者在岩石上捆绑一个火箭发动机,将其推向一个想要的方向。再或者发射一个大型太空船绕其运行,太空船的引力将会改变小行星绕太阳运转的轨道。The trouble is that many of these ideas rely on having plenty of warning. Even small asteroids are big, as 2012 DA14 shows.问题在于,这里面的很多主意都依赖于充足的预警时间,即使是处理如2012 DA14般的小块头小行星。That means shifting them at short notice is going to be difficult.这就意味着,在很短的预知时间下,将很难改变他们的轨道。When Americans National Research Council studied the problem in 2010, it came to the conclusion that even nuclear weapons would require warnings times measured in years or decades.当美国国家研究委员会在2010年研究这个问题时,得出一个结论:即使是使用核武器也需要数年甚至数十年的预警时间。Evacuation, it said, was the only feasible option for dealing with little warning. Others are more optimistic.委员会同时提到,在面对那些很难被辨认出而不期而至的小行星时,疏散是唯一可行的办法。The day before the explosion over Russia researchers at the University of California, Santa Barbara, proposed putting into orbit a solar-powered laser that could use its beam to vaporize the surface of an incoming asteroid and thus knock it off course, even at a few days notice.其他人要乐观一些。就在俄国上空的爆炸发生前一天,来自圣巴巴拉加利福尼亚大学的研究人员提出一个把太阳能激光器发射到小行星轨道的方案,使用激光蒸发掉小行星表面的物质。这样即使只有数天的预警时间,也能使其偏离轨道。Bet your life?用你的生命做赌注?Hard-nosed economists might wonder whether spending money on asteroid research-either for detection or deflection-is really worth it.精明实务的经济学家也许会怀疑在小行星研究上投资是否物有所值,不管是小行星探测或是轨道偏移。After all, for all their drama asteroid strikes are rare, and there are plenty of other threats to worry about.毕竟,小行星撞击是个非常戏剧性且罕见的,而我们还有众多其他的威胁需要担忧。But the relative lack of information makes the true risk difficult to calculate.但是由于信息的相对匮乏,真正的风险难以评估。An asteroid strike is an event with a low probability, but a high death toll when it does happen.小行星撞击是低概率事件,但是一旦发生,就意味着大量的死亡。That, as Dr Tonry points out, does funny things to risk calculations.士Tonry指出,这让计算风险变得有些奇异。Our best guess is that you can expect maybe 100 people a year to die from asteroid strikes, he says.他说,我们最好的估算是,每年大约会有100人死于小行星撞击,Of course, what that really means is that you might see 100,000 death every thousand years, or 100m every million.当然,实际上这意味着每隔数千年发生一次10万人的死亡,或者每百万年发生一次1亿人的死亡。After dodging two potential catastrophes in one day, the world may decide it is better to be safe than sorry.在一天之内躲过了两次可能的灾难之后,我们的世界也许会决定,安全总比遗憾好。 /201312/269271成都市生殖专业医院做白带常规阴道镜彩超多少钱 Finance and Economics;Spanish banks; False summit;财经;西班牙;远未结束;Mark down loans, raise capital, repeat;减少贷款,提高资金,重复此道;Like exhausted climbers nearing the summit only to find a higher peak beyond, Spains flagging banks face another push for the top. In February the Spanish government hoped at last to put an end to worries about lenders health when it asked them to set aside billions in provisions and to raise more capital. It also pushed for mergers to reduce capacity and improve margins in an overcrowded market.正如精疲力竭的攀登者接近峰顶时才发现前方还有座更高的山峰一样,西班牙疲弱的们面临着又一个困难。2月,西班牙政府要求按规定预留数十亿并筹集更多的资金,希望以此最终消除有关健康的担忧。政府还促使并购者们在过度拥挤的市场中减小规模,提高利润。These measures provide some comfort. Spains central bank says that since the middle of 2008, banks have set aside 112 billion Euro(148 billion Dollar) against loan losses. This year it asked them to set aside another 54 billion Euro in provisions and new capital (although this double-counted some write-downs that had aly taken place). With these plump cushions, Spains banks can shrug off losses amounting to about half of their loans to property developers. The IMF now reckons that Spains largest banks have enough capital to withstand most shocks, although its smaller and weaker ones remain vulnerable.这些举措带来了一些安慰。西班牙央行声称自从2008年中期以来,们已经预留了1120亿英镑(1480亿美元)来应对贷款损失。今年央行要求们再预留540亿英镑以及新的资金(尽管这样重复计算了有些已经发生的减记金额)。有了这些充足的缓冲,即使贷款损失高达房产开发商贷款总额的一半,西班牙的们也不屑一顾。现在国际货币基金组织认为西班牙的大们有足够的资金来抵御大部分冲击,尽管其较小较弱的依旧脆弱。European economy欧洲经济As a result of the write-downs, regulators have achieved one objective. Few investors now fret about property-development loans blowing up Spanish banks. The worry now is about all the other loans on banks balance-sheets, against which there are almost no provisions (see chart). Take residential mortgages, which have so far held up remarkably well. Less than 3% of residential mortgages have started to wobble, a surprise in a country where unemployment is close to 25%.监管者已通过减记达到了一个目标。现在很少有投资者担忧房产开发贷款会弄垮西班牙。现在的担忧是资产负债表上的其它贷款,而这些几乎没有预留资金。(见图表)。以目前为止表现还不错的住房按揭贷款为例,在一个失业率接近25% 的国家,只有不到3%的住房按揭贷款开始出现问题,这令人惊讶。Spanish officials argue that mortgage losses are so low because the loans were mostly issued to creditworthy borrowers with low loan-to-value ratios and no incentive to walk away from their debts. There was almost no subprime lending and little buy-to-let activity. Affordability has been helped by low interest rates.西班牙官员声称抵押贷款损失之所以如此之低是因为贷款大多发放给信誉良好的借款人,他们贷款价值比率较低,没有逃离其债务的动机。西班牙几乎没有次级贷款和随意贷款的行为。低利率也有助于确保付能力。Investors will take some convincing. “People just do not believe the numbers,” says one analyst. “There has been a lot of ‘extending and pretending or renegotiation of mortgages.” One mechanism by which banks are holding down bad loans is by encouraging struggling customers to switch from normal mortgages to ones where they repay only the interest. The latest data show that terms are being modified on some 26,000 mortgages a month.投资者们将会有些信。“人们只是不相信这些数字,”一位分析员这么说道。“有很多关于“扩大和假装”或是重新就抵押贷款进行谈判的说法”。阻止坏账上升的机制之一,就是鼓励那些苦苦挣扎的客户们从常规抵押贷款转向那种他们只需付利息的模式。最新的数据显示一个月之内就有26000份抵押贷款条约做了修改。The proportion of wobbly mortgages in Spain looks low when compared with those in Ireland. There the central bank and BlackRock, an asset manager, reckoned that actual lifetime losses on residential mortgages would range from 7% to 12% (meaning that rates of non-performing loans, some of which may in time start to perform again, could be higher still). Even if losses in Spain are far below those in Ireland, banks are still likely to need a lot more capital.与爱尔兰相比,西班牙的抵押贷款坏账比例看上去较低。爱尔兰央行以及某资金管理机构BlackRock认为,住房抵押贷款的实际寿命损失在7%至12%之间(意味着不良贷款率可能会更高)。即使西班牙的贷款损失远低于爱尔兰,们仍然可能需要更多的资金。Some investors reckon 60 billion-80 billion Euro is required to restore confidence. The IMF is coy about giving a number, but it too thinks more capital is needed, perhaps in asset-management companies set up to look after dud loans. But attracting private capital will be tough. That would pass the problem to the Spanish government, whose finances are under scrutiny, or to Europes bail-out funds, whose firepower is more limited than advertised.有些投资者认为重塑信心需要600-800亿英镑。对此谨慎的国际货币基金组织未给出具体数字,但它也认为需要更多的资金,也许正是那些用来监管不良贷款的资产管理公司需要更多的资金。但是吸引私人资本将会很难。这将会把问题转嫁给已接受财政审查的西班牙政府,或是火力比宣传的更为有限的欧洲纾困基金。 /201305/240003成都省第十人民医院院长是谁

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成都生殖专科是私立的还是公立的Gun control管制Armed robbery持抢劫Quietly, and rather politely, Britain is getting a gun lobby不知不觉中,英国成为倡议管制的一大阵营ORYX and buffalo heads stare glumly from the walls of James Purdey amp; Sons, a swanky London gunmaker. In cases beneath them stand some of the priciest weapons in Britain. The firms elaborately engraved shotguns take up to two years to produce and cost at least 80,000. Many customers buy a pair.大羚羊及野牛满是忧郁地凝视着普德莱家族的围墙,这是伦敦一个有着显著地位的生产者。坐拥英国一些最昂贵的武器。该公司精巧设计的猎两年时间里产出并消耗了最少十三万五千英镑。大客户都是一次性购买一副。Shooting is an expensive hobby, even without so extravagant a weapon. But licensing a gun is cheap. Owners pay only 50 to register for five years, a fee that has not risen since 2001. Police chiefs say the cash they collect covers barely a quarter of what it costs them to run the licensing scheme, and that they are spending more than 17m a year to cover the shortfall.即使不怎么昂贵,射击仍是一项奢侈的爱好。但是获得持书就相对便宜多了。持有者只需付50英镑就可获得5年有效期的持,这个费用自2001年以来再也没涨过。警察局长们说,他们收取的这些费用只够办理许可程序花费的四分之一,因此不得不付一千七百万来弥补短缺的。That is not a big number, but it rankles at a time of austerity, the police have suffered from more than other public services. The problem is not just that inflation has eroded the value of the fee, says Andy Marsh of Hampshire Constabulary. Better monitoring of gun owners has made the system more expensive, and the workload is growing as gun ownership creeps up. Since fees were set in 2001 the number of guns held by civilians in England and Wales has risen by 14% to 1.8m, the highest number since detailed record-taking started two decades ago.虽然数目不大,但是在紧缩时期更是雪上添霜,因为警察们比其它公共务行业工作人员付出的还要多。问题的关键在于,并不是通货膨胀侵蚀了许可费的价值,汉普郡警察安迪沼泽如是说。更好的持有者的监视使得这个系统费用更加的昂贵,费用工作量也随着持者的不断增加而变大。自从2001年制定许可费以来,在英格兰和威尔士公民持的数量以百分之十四增长至一百八十万,为自开始记录持人数二十年以来的最高值。These healthy figures surprise those who thought strict gun laws brought in after a mass shooting in Scotland in 1996 would fatally wound Britains shooting culture. That horror, and the ban on handguns that followed, encouraged gun ownership to decline for five consecutive years. But a gradual increase in the popularity of rifles, both for shooting targets and for killing deer and other animals, has since reversed the trend. Novices find it fairly easy to get a licence: despite rigorous checks police refuse less than 2% of the applications they receive.、这些持续增长的数据使得人们感到无比的惊讶,他们认为在1996年苏格兰群体击事件之后引入严格的法律将对英国的文化以致命打击。那次惨案和之后的手禁令连续5年鼓励减少持有者数量。但是步流行的持续增加,射击的靶和猎杀鹿及其他动物自那之后出现逆向增长。新手们发现获得持许可非常容易:尽管经过严格的审查,警察们回绝了他们收到的至少百分之二的应用申请。As their ranks have swelled, political support for shooters has rebounded. Among the many populist pledges put forward by Nigel Farage, the leader of the UK Independence Party, is a promise to loosen gun laws if elected. Conservative bigwigs probably think that a small public subsidy for gun owners is a meagre price to placate voters in their rural heartlands—especially given that the Tories have not yet held a promised vote on repealing the ban on fox hunting for fear that MPs would vote to uphold it. In September a cabinet subcommittee blocked a plan, backed by the Home Office, to push up the gun licence fee.随着持人数量的不断膨胀,对持者的政治持也获得了反弹。奈杰尔·法拉吉推进的多数平民誓言中,英国独立党领袖许诺如果当选的话,将放宽管制。保守派的大亨们很可能会认为对持者的一小点政府补助是对在他们农村中心地带的选民们一种低代价的慰藉,尤其是考虑到托利党出于担心议员们投票的持而还没有接受废除猎狐禁令的选票。九月一次由内政部做东的内阁小组会议上阻止了关于提高许可费用的计划。Britains discreet but well-connected shooting lobby accepts that sooner or later a fee increase is inevitable. It demands that police cut bureaucracy from the licensing process before asking gun owners to stump up more. This stubbornness seems to have prodded officers into patching the system up, but it would be wise to wave through a deal. Shooting down a small rise this year would probably mean having to stomach a loftier one in future, especially if the Tories lose the next general election. That would be a worthless trophy.英国的谨慎而又有着良好关系网的射击说客已然认识到许可费提高是不可避免的。这就需要警察们在要求持有者多掏费用之前,放下他们在许可办理过程中的官僚主义。这一棘手之事似乎鞭策着官员们来修补整个行政系统,但是通过交易来平息这一波折显得更加明智。今年压制了小规模的持有者增长,意味着因小失多,将来可能不得不接受更多损失,尤其是当托利党下次竞选中失利。这将是件毫无价值的战利品。 201406/303367 Most of the time, volcanoes look like other mountains:大多数时候,火山看起来和其他的山体没有两样:solid,serene, capped with snow–a nice place to go camping.固体,平静,被积雪覆盖-露营的不错选择。Unless, of course, it happens to explode and pour molten lava all over your campsite!除非,当然,它突然喷发,熔浆覆盖你的营地。Wouldnt itbe nice if we could predict when a volcano was about to erupt?如果我们能够预测火山什么时候会喷发,是不是更好呢?Scientists have recently taken a big step closer toward doing just this.科学家们最近在此领域的研究取得了进展。Lets look inside a volcano.让我们一起来看看火山的内部结构吧!At the center is a reservoir of molten rock, known as magma.中心是一个熔岩的“液态区”,叫岩浆。This magma is very hot, and under a lot of pressure.岩浆温度很高,并且处于一定的压力之下。When rainwater seeps into cracks in themountain, the magma turns it into steam and forces it out again.当雨水渗入山缝后,岩浆将其蒸发为水蒸汽,又让它排放出来。The magma also vents awayhot gasses through these same cracks.岩浆也同样通过这些山缝散发一些热气。This is a volcanos normal state.这是一座火山的正常状态。When gasses and steam vent from a volcanos cracks, itsprobably not about to erupt.当气体和蒸汽可以从火山的裂缝排放时,它可能并不会喷发。Sometimes, however, the top layer of magma can cool, and form ahard crust over the rest of the molten rock.然而,有时顶层的岩浆会冷却,并在外部形成一个坚硬的壳。When this happens, rainwater is able to collect in thecracks without evaporating, and this water captures a lot of gasses that would ordinarily vent fromthe magma.这时,雨水聚集在岩缝中,不能蒸发。这些雨水阻止了岩浆热气的排放。Scientific instruments inside the volcanos cracks record a sudden drop in temperature, and much less volcanic gas.在山缝中的科学仪器记录到了温度的陡然下降,和火山气体的减少。This is a warning sign for an imminent eruption.这是即将喷发的一个预兆。冷却的岩浆壳让内部的液体压力增大。That cool magmaseal allows pressure to build upinside the liquid magma, much like your thumb over the top of a shaken soda bottle will seal inthe pressure.就像把你的拇指放在被摇过的苏打水瓶口上,使其密封,增加内部压力。When that magmaseal gives way its like taking your thumb off the top of the bottle, and you dont want to be camping on the volcano when that happens!岩浆上部的密封壳被冲开时,就像你的拇指从苏打水瓶上拿开的时候一样,在这种情况下,你就不会想要在火山上露营了。 /201409/326986甘孜州妇幼保健院有四维彩超吗温江区中心医院妇科专家大夫



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